The present invention relates to an apparatus for measuring outdoor temperature and humidity.
The commonly used apparatus for measuring outdoor temperature and humidity usually include a main body hanging on an indoor wall or nearby a window, and have an electric wire extending from the main body to connect a temperature and humidity sensor located outdoors. The main body has temperature and humidity measuring circuits and display circuits to measure temperature and humidity values. To install the apparatus, a hole is drilled on the wall or a window for hanging the temperature and humidity sensor, or the window is opened for a slit for installing the sensor outdoors.
Another measuring apparatus include a main device and a secondary device. The main device has a display unit and a radio receiving circuit, and the secondary device has temperature and humidity measuring circuits, and a radio transmission circuit. When in use, the main device is installed indoors and the secondary device is installed outdoors. The temperature and humidity measuring circuits in the secondary device measure outdoor temperature and humidity values, and emits the measured values in radio fashion. The radio receiving circuit in the main device receives the transmitted temperature and humidity values and displays on the display unit.
The apparatus set forth above still have drawbacks, notably:
a. The first type of measuring apparatus requires to drill a hole on the wall, or to open a slit on the window. Moreover, the main body has to be hung on the wall or nearby the window. Installation is quite cumbersome and time-consuming. In addition, opening a slit on the window results in poor insulation, and rainwater tends to seep in and outdoor noises tend to invade into rooms. It also results in leakage of air conditioning and waste of energy.
b. The second type of measuring apparatus requires the secondary device to transmit temperature and humidity values by radio. It consumes a lot of electric energy, and requires to replace batteries frequently. Moreover, the radio transmission tends to cause radio frequency disturbances and has potential hazards to human body.
Therefore the primary object of the invention is to resolve aforesaid disadvantages. The invention couples temperature and humidity sensors and a measuring circuit in a box type body in an integrated forming fashion. The body may be freely placed outside a window to perform measuring function without skilled professionals to do installation or wiring. And outdoor temperature and humidity can be directly read indoors.
Another object of the invention is to provide an outdoor temperature and humidity measuring apparatus that has a cover plate located on a rear side of the body to prevent temperature and humidity measuring sensors from affecting by sun radiation heat to achieve accurate measurement of outdoor air temperature and humidity.
A further object of the invention is to provide an outdoor temperature and humidity measuring apparatus that is controlled by a microprocessor and has a display screen to provide indications with desired patterns.